Centrifuges are used to separate constituent elements using rotational energy.
Centrifuges commonly include a rotor that rotates about its center and a plurality of adaptors that are commonly inserted into the rotor in a circular configuration. Each adaptor has an opening into which a specimen tube may be inserted.
Centrifuges operate at a variety of speeds and in a variety of environments. For example. some centrifuges used in laboratory environments are run at relatively low speeds, i.e., 15,000 rpm, and under atmospheric conditions.
However, when a centrifuge is run under these circumstances, a problem is created unless every adaptor has a tube inserted. In particular, when an empty adaptor is rotated at the above mentioned speed and in the presence of air, an objectionable high pitch whistle is created. This whistle may be very distracting in a laboratory environment where other activities are ongoing. In addition, this whistle has been found to be especially audible and enervating to some workers.
It is possible to eliminate this whistle, for example, by always running the centrifuge with tubes in place or by placing a lid over every empty adaptor in the rotor. However, such approaches are inconvenient and may cause the rotor to be unbalanced.